Civil Engineering Professional Engineer Practice Exam

What characterizes a dynamic load?

1. Consistent weight over time

2. A sudden impact on the structure

3. Gradual pressure from environmental forces

4. A load that is always present

The correct answer is: A sudden impact on the structure

A dynamic load is characterized by a sudden or changing force applied to a structure, which distinguishes it from static loads that remain constant over time. This sudden impact can be the result of various factors, such as forces generated by moving vehicles, wind gusts, seismic activities, or other changing conditions. The key aspect of dynamic loads is their potential to cause significant stress and strain in structures due to the variations in magnitude and direction of the load over time. In contrast, a consistent weight over time would categorize as a static load, while gradual pressure from environmental forces also relates to static or gradually varying loads rather than the abrupt changes associated with dynamic loads. A load that is always present does not convey the variability related to dynamic loading scenarios. Therefore, the correct choice highlights the nature of dynamic loads as those involving sudden impacts, which can critically influence the design and analysis of civil engineering structures.